On-duty NYPD personnel are involved in about 3,900 traffic collisions each year, according to data provided by the department in response to Streetsblog’s freedom of information request.

From 2011 through 2015, there were 19,591 collisions involving NYPD vehicles. That’s an average of 3,918 crashes annually, or between 10 and 11 collisions a day. (NYPD did not provide information on the severity of crashes, but typically, about 60 percent of all crashes in New York City result in minor injuries, about 17 percent cause more serious injuries or fatalities, and the remainder damage property.)

The annual total ranged from 3,783 crashes in 2014 to 4,019 in 2011. In 2015, the most recent year with available data, there were 3,852 NYPD collisions.

To reduce injuries and deaths from collisions involving city fleet vehicles, in 2014 the Department of Citywide Administrative Services began collecting and sharing data on such crashes. NYPD was the only agency not to provide DCAS with data, which made it impossible for the city and the public to get a complete picture.

Using the numbers from NYPD and data compiled by DCAS, we can now roughly situate police collisions within the context of the entire city fleet:

In 2015, DCAS reported 6,132 collisions involving all city agencies other than NYPD [PDF]. The same year, NYPD reported 3,852 collisions, or 38 percent of all crashes in the city fleet. That is somewhat higher than NYPD’s 33 percent share of all city vehicles.

The department’s crash rate was 3.9 collisions per 100,000 miles in FY 16, up from 3.2 collisions per 100,000 miles in FY 15, according to the Mayor’s Management Report. (The DCAS report doesn’t include per-mile numbers, so we can’t make a comparison to other agencies.)

It’s unknown how many police collisions result in death, injury, or property damage. Annual reports from the city comptroller’s office consistently show that NYPD leads city agencies in legal settlement claims, some of which stem from vehicle crashes. That’s as close as the public gets to gauging the human toll of NYPD traffic collisions, including police chases that kill innocent bystanders.

With NYPD involved in more collisions than any other city agency, the department should open the books on police crashes, and let the public know how it plans to get those numbers down.